When connecting a trailer to a towing vehicle it is commonly desirable to check that the turn and brake indicator signals to the trailer are functioning properly prior to use for safety concerns. Inspection typically requires two persons such that one person can activate the signals from the vehicle operator cab while the other person can visually inspect the indicator on the rear of the trailer. In commercial trucking in particular, routinely inspecting the operation of the indicators is generally part of a required safety inspection by the operator before each trip. Due to the difficulty in a single person both activating and inspecting the condition of the indicators, it occasionally leads to some operators not properly checking the condition of the trailer such that the safety of the operation of the trailer may be compromised.
US Patent Application Publication 2009/0056432 by Steininger discloses a remotely operated brake tester in the form of an actuator which physically depresses the brake pedal in the operator cab when activated by remote. While this permits checking of the brake indicators by a single operator, the actuator is cumbersome to install for each test as it must be removed for normal operation of the vehicle. Furthermore the operator must still make several trips between the operator cab and the rear of the trailer for checking other indicators such as the turn indicators in addition to the brake indicators.
U.S. Pat. No. 6,530,261 by Foster, U.S. Pat. No. 6,154,035 by Aguirre et al., U.S. Pat. No. 5,602,482 by Gutierrez and U.S. Pat. No. 5,668,314 by Jones disclose various brake test devices including their own respective power and compressed air supplies for direct connection to a trailer with air brakes to test various conditions of the trailer. Testing is limited to the trailer such that there is no testing provided for the connections between the vehicle and the trailer as required for a safety inspection prior to each trip with a towing vehicle and trailer connected thereto.
U.S. Pat. No. 6,817,234 by Maresko and U.S. Pat. No. 5,467,645 by Skorupski et al. disclose additional examples of brake testing systems, however neither permit remote checking of all indicators on a trailer connected to a towing vehicle prior to operation of the vehicle.
Overall no prior art device readily allows a single operator to check all turn and brake indicators on a vehicle and a connected trailer in a single pass about the vehicle during a pre-trip safety inspection.